1. Field of the Invention
The invention relates to a sealed battery and a manufacturing method thereof. More particularly, the invention relates to a sealed battery in which a lid is fit into a stepped opening of a battery can and welded thereto, as well as a manufacturing method of this sealed battery.
2. Description of Related Art
An apparatus that uses a battery is typically provided with a rectangular parallelepiped battery housing portion, and a rectangular sealed battery is used to effectively utilize the volume of the battery housing portion. Japanese Patent Application Publication No. 2001-135282 (JP 2001-135282 A), for example, describes one manufacturing method of a sealed battery that involves fitting a lid into a stepped opening of a battery can that houses a power generating element, and welding it (i.e., the lid) thereto.